Wavelength division multiplexed (WDM) optical networks are known where light of multiple wavelengths is dispersed such that each wavelength of light is spatially separated from every other wavelength of light. A plurality of signals having wavelengths of different lengths can be combined for transmission over a single fiber optic cable. For optical transmission systems such as in a backbone network with a great demand for communication, a further increase in capacity has been found by reducing the optical wavelength spacing of a plurality of signal channels to increase the degree of multiplexing. WDM processing with a higher degree of multiplexing is called dense wavelength division multiplexing (DWDM).
Also, it is known in optical transmission systems in which there is less demand for communication that the degree of multiplexing can be decreased by increasing the optical wavelength spacing of a plurality of signal channels. This has the effect of reducing costs for the system components. WDM processing with a lower degree of multiplexing is called coarse wavelength division multiplexing (CWDM). In a CWDM system, inexpensive optical components can be used.
In WDM systems, and in particular CWDM systems, a variety of different media signals communicated on cables including coaxial, twisted pair (shielded and unshielded), and optical, may be converted to, for example, a standard optical format. WDMs including CWDMs are utilized to process these signals for transmission over fiber networks. In the case of multimode signals on fiber optic cables, WDMs can be used to process the signals for transmission on a multiplexed single cable system including a single mode fiber.
Because WDM systems involve multiplexing of multiple signals on multiple cables, there is a need for cable management. In addition, there is a need to provide modularity to allow for ease in upgrading to additional capacity when desired. Further, it is desirable to provide thermal management to dissipate heat generated by the WDM systems.